DESCRIPTION

Flublok [Influenza Vaccine] is a sterile, clear,
colorless solution of recombinant hemagglutinin (HA) proteins from three
influenza viruses for intramuscular injection. It contains purified HA proteins
produced in a continuous insect cell line (expresSF+®) that is derived
from Sf9 cells of the fall armyworm, Spodoptera frugiperda (which is
related to moths, caterpillars and butterflies), and grown in serum-free medium
composed of chemically-defined lipids, vitamins, amino acids, and mineral
salts. Each of the three HAs is expressed in this cell line using a baculovirus
vector (Autographa californica nuclear polyhedrosis virus), extracted
from the cells with Triton X-100 and further purified by column chromatography.
The purified HAs are then blended and filled into single-dose vials.

Flublok is standardized according to United States Public
Health Service (USPHS) requirements. For the -2015-2016 influenza season it is
formulated to contain 135 mcg HA per 0.5 mL dose, with 45 mcg HA of each of the
following 3 influenza virus strains: A/California/7/2009 (H1N1), A/Hong
Kong/4801/2014 (H3N2), and B/Brisbane/60/2008.

Flublok contains no egg proteins, antibiotics, or
preservatives. The stoppers used for the single-dose vials are not made with
natural rubber latex.

Indications & Dosage

INDICATIONS

Flublok is a vaccine indicated for active immunization
against disease caused by influenza A virus subtypes and influenza type B virus
contained in the vaccine. Flublok is approved for use in persons 18 years of
age and older.

DOSAGE AND ADMINISTRATION

Dosage

Administer Flublok as a single 0.5-mL dose.

Administration

Shake the single-dose vial gently before withdrawing the
vaccine dose.

Parenteral drug products should be inspected visually for
particulate matter and discoloration prior to administration whenever solution
and container permit. If either of these conditions exists, the vaccine should
not be administered.

The preferred site for injection is the deltoid muscle.
Administration is by sterile needle and syringe.

Flublok should not be mixed with any other vaccine in the
same syringe or vial.

HOW SUPPLIED

Dosage Forms And Strengths

Flublok is a sterile solution supplied in single-dose
vials, 0.5 mL.

Flublok is supplied as a single-dose, 0.5 mL vial in a 10
vial carton:

SIDE EFFECTS

In adults 18 through 49 years of age, the most common
( ≥ 10%) injection-site reaction was pain (37%); the most common
( ≥ 10%) solicited systemic adverse reactions were headache (15%), fatigue
(15%) and muscle pain (11%). (6.1)

In adults 50 through 64 years of age, the most common
( ≥ 10%) injection site reaction was pain (32%); the most common
( ≥ 10%) solicited systemic adverse reactions were headache (17%), fatigue
(13%), and muscle pain (11%). (6.1)

In adults 65 years of age and older, the most common
( ≥ 10%) injection site reaction was pain (19%); the most common
( ≥ 10%) solicited systemic adverse reactions were fatigue (13%) and
headache (10%). (6.1)

Clinical Trials Experience

Because clinical studies are conducted under widely varying
conditions, adverse reaction rates observed in the clinical studies of a
vaccine cannot be directly compared to rates in the clinical studies of another
vaccine and may not reflect the rates observed in clinical practice.

Flublok has been administered to and safety data
collected from 2497 adults 18 through 49 years of age, 972 adults 50 through 64
years of age, and 1078 adults aged 65 years and older enrolled in five
randomized, placebo- or active-controlled clinical trials. Clinical safety data
for Flublok are presented from four clinical trials (Studies 1, 2, 3, and 4).
Data from a placebo-controlled trial in adults 18 through 49 years of age
(Study 1) are presented, followed by data pooled according to age group from
Studies 2 and 4 (adults 50 through 64 years of age) and Studies 3 and 4 (adults
aged 65 years and older). Reactogenicity data from a small Phase 2 trial (Study
5) in adults 18 through 49 years of age, 153 of whom received Flublok 135mcg,
are not presented. However, subjects from Study 5 are included in the
description of deaths and serious adverse events (SAEs). In all studies local
(injection site) and systemic adverse reactions were solicited with the use of
a memory aid for 7 days following vaccination, and unsolicited adverse reactions
were collected for 28-30 days post-vaccination. In Studies 1- 3 and 5, SAEs
were collected for 6 months post-vaccination via clinic visit or telephone
follow up on Day 28, telephone follow up on Day 180, or by spontaneous
reporting. Study 4 collected SAEs through 30 days following receipt of vaccine.
Study 4 also actively solicited pre-specified common hypersensitivity-type
reactions through 30 days following receipt of vaccine as a primary endpoint.

Study 1 included 4648 subjects 18 through 49 years of age
for safety analysis, randomized to receive Flublok (n=2344) or placebo (n=2304)
(1) (see Clinical Studies).

Study 2 included 602 subjects 50 through 64 years of age
for safety analysis, randomized to receive Flublok (n=300) or another U.S.-licensed
trivalent influenza vaccine (Fluzone, manufactured by Sanofi Pasteur, Inc.) as
an active control (n=302) (2) (see Clinical Studies).

Study 3 included 869 subjects aged 65 years and older for
safety analysis, randomized to receive Flublok (n=436) or another U.S.-licensed
trivalent influenza vaccine (Fluzone) as an active control (n=433) (3) (seeClinical
Studies).

Study 4 included 2627 subjects aged 50 years and older
for safety analysis, randomized to receive Flublok (n=1314) or another U.S.-licensed
trivalent influenza vaccine (Afluria, manufactured by bioCSL Pty Ltd.) as an
active control (n=1313). Among subjects 50 through 64 years of age, 672
received Flublok and 665 received Afluria. Among subjects aged 65 years and
older, 642 received Flublok and 648 received Afluria (see Clinical Studies).

In a clinical trial of adults 18-49 years of age (Study
1, Table 1) the mean age of participants was 32.5 years, 59% were female, and
67% were Caucasian (see Clinical Studies).

Table 1: Frequency of Solicited Local Injection Site
Reactions and Systemic Adverse Reactions within 7 Days of Administration of
Flublok or Placebo in Adults 18-49 Years of Age, Study 1, Total Vaccinated
Cohort1,2,3

Local

Flublok
N=2272

Placebo
N=2231

%

%

Any

Mod4

Sev4

Any

Mod4

Sev4

Pain

37

2

< 1

8

< 1

< 1

Redness

4

< 1

< 1

2

< 1

< 1

Swelling

3

< 1

< 1

2

< 1

< 1

Bruising

3

< 1

< 1

3

< 1

< 1

Systemic

%

%

Headache

15

3

< 1

16

3

< 1

Fatigue

15

3

< 1

14

3

< 1

Muscle Pain

11

2

< 1

7

< 1

< 1

Nausea

6

1

< 1

5

1

< 1

Joint pain

4

< 1

< 1

4

< 1

< 1

Chills

3

< 1

< 1

3

< 1

< 1

Fever‡

< 1

< 1

< 1

< 1

< 1

< 1

NOTE: Data based on the most severe response reported by
subjects. Results ≥ 1% reported to nearest whole percent; results > 0
but < 1% reported as < 1%.
‡ Fever defined as ≥ 100.4°F (38°C). Mild ( ≥ 100.4° to < 101.1°F);
Moderate ( ≥ 101.2°F to < 102.2°F); Severe ( ≥ 102.2°F) 1 Total Vaccinated Cohort is defined as all randomized subjects who
received study vaccine according to the treatment actually received and who
provided data. 2 Study 1 is registered as NCT00539981 under the National Clinical
Trials registry. 3 Denominators for Study 1: The total number of enrolled,
randomized, and vaccinated subjects was 2344 in the Flublok group and 2304 in
the placebo group. For all categories except fever, the number of subjects with
missing values was 72 in the Flublok group and 73 in the Placebo group so that
these denominators are 2272 and 2231 respectively. For fever, 89 Flublok
recipients and 104 Placebo recipients were missing data, making these
denominators 2255 and 2200 respectively. 4 Moderate = had it, and it was bad enough to prevent a significant
part of usual activities; Severe = had it, and it prevented most or all of
normal activities, or had to see a doctor for prescription medicine.

Across three clinical trials (Studies 2 - 4, Tables 2 and
3) a total of 2050 adults age 50 years and older received Flublok and 2048
received a U.S.-licensed IIV3 comparator. The mean age of Flublok study
participants was 65 years; 56% were female and 80% were Caucasian (see Clinical
Studies).

The incidence of solicited reactogenicity differed
between adults 50 through 64 years of age and adults aged 65 years and older.
Therefore, data from Studies 2, 3, and 4 were pooled according to age group and
are presented separately (Tables 2 and 3).

Most events in both age groups were mild in severity.

Table 2: Frequency of Solicited Local Injection Site
Reactions and Systemic Adverse Reactions within 7 Days of Administration of
Flublok or Comparator in Adults 50-64 Years of Age, Studies 2 and 4, Total
Vaccinated Cohort1,2

Flublok
N=972

IIV32
N=967

Any

Mod3

Sev3

Any

Mod3

Sev3

Local

%

Pain

32

2

< 1

37

< 1

0

Firmness/Swelling

7

2

< 1

6

1

< 1

Redness

6

2

< 1

5

1

< 1

Systemic

%

Headache

17

4

< 1

16

3

< 1

Fatigue

13

3

< 1

17

3

< 1

Muscle Pain

11

2

< 1

11

2

< 1

Joint Pain

8

2

< 1

8

2

< 1

Nausea

6

1

0

5

< 1

< 1

Shivers/Chills

5

1

0

4

< 1

< 1

Fever‡

< 1

< 1

< 1

< 1

0

0

NOTE: Data based on the most severe response reported by
subjects. Results ≥ 1% reported to nearest whole percent; results > 0
but < 1% reported as < 1%.
‡ Fever defined as ≥ 100.4°F (38°C). Mild ( ≥ 100.4° to < 101.1°F);
Moderate ( ≥ 101.2°F to < 102.2°F); Severe ( ≥ 102.2°F) For fever, 12
Flublok recipients and 5 IIV3 recipients were missing data, making these
denominators 964 and 962, respectively. 1 Total Vaccinated Cohort is defined as all randomized subjects who
received study vaccine according to the treatment actually received and who
provided data.2 Pooled Data from Studies 2 and 4. For
Studies 2 and 4, the U.S.-licensed IIV3 comparators were Fluzone and Afluria,
respectively. Studies 2 and 4 are registered as NCT00539864 and NCT01825200, respectively,
under the National Clinical Trials registry. 3 Moderate = had it, and it was bad enough to prevent a significant
part of usual activities; Severe = had it, and it prevented most or all of
normal activities, or had to see a doctor for prescription medicine.

Table 3: Frequency of Solicited Local Injection Site
Reactions and Systemic Adverse Reactions within 7 Days of Administration of
Flublok or Comparator in Adults ≥ 65 Years of Age, Studies 3 and 4, Total
Vaccinated Cohort 1,2

Flublok
N=1078

IIV32
N=1081

Any

Mod3

Sev3

Any

Mod3

Sev3

Local

%

Pain

19

< 1

< 1

20

< 1

< 1

Redness

7

1

< 1

7

1

1

Firmness/Swelling

7

2

< 1

7

< 1

< 1

Systemic

%

Fatigue

13

3

< 1

15

2

< 1

Headache

10

< 1

< 1

9

1

< 1

Muscle Pain

8

2

< 1

8

1

< 1

Joint Pain

6

1

< 1

6

1

< 1

Shivers/Chills

5

< 1

< 1

5

< 1

< 1

Nausea

4

< 1

< 1

3

< 1

< 1

Fever‡

3

< 1

< 1

2

0

0

NOTE: Data based on the most severe response reported by
subjects. Results ≥ 1% reported to nearest whole percent; results > 0
but < 1% reported as < 1%.
‡Fever defined as ≥ 100.4°F (38°C). Mild ( ≥ 100.4° to < 101.1°F);
Moderate ( ≥ 101.2°F to < 102.2°F); Severe ( ≥ 102.2°F) 1 Total Vaccinated Cohort is defined as all randomized subjects who
received study vaccine according to the treatment actually received and who
provided data. 2 Pooled Data from Studies 3 and 4. For Studies 3 and 4, the
U.S.-licensed IIV3 comparators were Fluzone and Afluria, respectively. Studies
3 and 4 are registered as NCT00395174 and NCT01825200, respectively, under the
National Clinical Trials registry. 3 Moderate = had it, and it was bad enough to prevent a significant
part of usual activities; Severe = had it, and it prevented most or all of
normal activities, or had to see a doctor for prescription medicine.

Among adults 18-49 years of age (Studies 1 and 5 pooled),
through 6 months post-vaccination, two deaths were reported, one in a Flublok recipient
and one in a placebo recipient. Both deaths occurred more than 28 days
following vaccination and neither was considered vaccine-related. SAEs were
reported by 32 Flublok recipients and 35 placebo recipients. One SAE in a
Flublok recipient was assessed as possibly related to the vaccine:
pleuropericarditis with effusions requiring hospitalization and drainage. No
specific cause was identified. The patient recovered.

Among adults 50-64 years of age (Studies 2 and 4 pooled),
through up to 6 months or 30 days, post-vaccination, respectively, there were
no deaths; SAEs were reported by 10 subjects, 6 Flublok recipients and 4 IIV3
recipients. One of the SAEs, vasovagal syncope following injection of Flublok,
was considered related to administration of study vaccine. Among adults 65
years of age and older (Studies 3 and 4 pooled), through up to 6 months or 30
days post-vaccination, respectively, there were 4 deaths, 2 in Flublok
recipients and 2 in IIV3 recipients. None were considered related to the study
vaccines. SAEs were reported from 80 subjects, 37 Flublok recipients, 43 in
IIV3 recipients. No SAEs were considered related to the study vaccines.

Among adults 50-64 years of age (Studies 2 and 4 pooled),
the most frequent unsolicited adverse events, occurring in 1% of subjects, were
diarrhea and cough. Among adults ≥ 65 years of age (Studies 3 and 4
pooled), the most frequent unsolicited adverse events, occurring in 1% of
subjects, were nasopharyngitis and cough.

Among adults 50 years of age and older (Study 4) for whom
the incidence of rash, urticaria, swelling, non-pitting edema, or other
potential hypersensitivity reactions were actively solicited for 30 days
following vaccination, a total of 2.4% of Flublok recipients and 1.6% of IIV3
recipients reported such events over the 30 day follow-up period. A total of
1.9% and 0.9% of Flublok and IIV3 recipients, respectively, reported these
events in the 7 days following vaccination. Of these solicited events, rash was
most frequently reported (Flublok 1.3%, IIV3 0.8%) over the 30 day follow-up
period.

Postmarketing Experience

The following events have been spontaneously reported
during post approval use of Flublok. They are described because of the temporal
relationship, the biologic plausibility for a causal relationship to Flublok,
and their potential seriousness. Because these events are reported voluntarily
from a population of uncertain size, it is not always possible to reliably
estimate their frequency or establish a causal relationship to vaccine exposure.

Immune system disorders: anaphylaxis, anaphylactoid
reactions, allergic reactions, and other forms of hypersensitivity.

Drug Interactions

DRUG INTERACTIONS

Data evaluating the concomitant administration of Flublok
with other vaccines are not available.

WARNINGS

PRECAUTIONS

Managing Allergic Reactions

Appropriate medical treatment and supervision must be
available to manage possible anaphylactic reactions following administration of
the vaccine.

Guillain Barré Syndrome

The 1976 swine influenza vaccine was associated with an increased frequency
of Guillain-Barré Syndrome (GBS). Evidence for a causal
relation of GBS with other influenza vaccines is inconclusive; if an excess risk
exists, it is probably slightly more than one additional case per 1 million
persons vaccinated. If GBS has occurred within 6 weeks of receipt of a prior
influenza vaccine, the decision to give Flublok should be based on careful
consideration of the potential benefits and risks.

Altered Immunocompetence

If Flublok is administered to immunocompromised
individuals, including persons receiving immunosuppressive therapy, the immune
response may be diminished.

Limitations Of Vaccine Effectiveness

Nonclinical Toxicology

Flublok has not been evaluated for carcinogenic or mutagenic
potential, or for impairment of male fertility in animals. A developmental
toxicity study conducted in rats vaccinated with Flublok revealed no evidence
of impaired female fertility (see Pregnancy).

Use In Specific Populations

Pregnancy

Pregnancy Exposure

Pregnancy outcomes in women who have been exposed to
Flublok during pregnancy are being monitored. Contact: Protein Sciences
Corporation by calling 1-888-855-7871.

Risk Summary

All pregnancies have a risk of birth defect, loss, or
other adverse outcomes. In the U.S. general population, the estimated
background risks of major birth defects and miscarriage in clinically
recognized pregnancies are 2% to 4% and 15% to 20%, respectively. Available
data on Flublok administered to pregnant women are insufficient to inform
vaccine-associated risks in pregnant women.

A developmental study of Flublok has been performed in
rats administered 0.5 mL (divided) of Flublok prior to mating and during
gestation. This study revealed no evidence of harm to the fetus due to Flublok
(see Data).

Clinical Considerations

Disease-associated Maternal and/or Embryo/Fetal Risk

Pregnant women are at increased risk of complications
associated with influenza infection compared to non-pregnant women. Pregnant
women with influenza may be at increased risk for adverse pregnancy outcomes,
including preterm labor and delivery.

Data

Animal

In a developmental toxicity study, female rats were
administered 0.5 mL (divided) of Flublok by intramuscular injection twice prior
to mating (35 days and 14 days prior to mating) and on gestation Day 6. No
vaccine-related fetal malformations or variations and no adverse effects on
pre-weaning development were observed in the study.

Lactation

Risk Summary

It is not known whether Flublok is excreted in human
milk. Data are not available to assess the effects of Flublok on the breastfed
infant or on milk production/excretion.

The developmental and health benefits of breastfeeding
should be considered along with the mother's clinical need for Flublok and any
potential adverse effects on the breastfed child from Flublok or from the
underlying maternal condition. For preventive vaccines, the underlying
condition is susceptibility to disease prevented by the vaccine.

Pediatric Use

Data from a randomized, controlled trial demonstrated
that children 6 months to less than 3 years of age had diminished hemagglutinin
inhibition (HI) responses to Flublok compared to a U.S.-licensed influenza
vaccine approved for use in this population, strongly suggesting that Flublok
would not be effective in children younger than 3 years of age (6). Safety and
effectiveness of Flublok have not been established in children 3 years to less than
18 years of age.

Geriatric Use

Data from an efficacy study (Study 6), which included
1759 subjects ≥ 65 years and 525 subjects ≥ 75 years who received
Flublok Quadrivalent, are insufficient to determine whether elderly subjects
respond differently from younger subjects (See Clinical Studies). The
efficacy of Flublok Quadrivalent is relevant to Flublok (trivalent formulation)
because both vaccines are manufactured using the same process and have
overlapping compositions.

CONTRAINDICATIONS

CLINICAL PHARMACOLOGY

Mechanism Of Action

Flublok contains recombinant HA proteins of the three
strains of influenza virus specified by health authorities for inclusion in the
annual seasonal vaccine. These proteins function as antigens which induce a
humoral immune response, measured by hemagglutination inhibition (HI)
antibody).

Antibodies against one influenza virus type or subtype
confer limited or no protection against another. Furthermore, antibodies to one
antigenic variant of influenza virus might not protect against a new antigenic
variant of the same type or subtype. Frequent development of antigenic variants
through antigenic drift is the virologic basis for seasonal epidemics and the
reason for the usual replacement of one or more influenza virus strains in each
year's influenza vaccine. Therefore, influenza vaccines are standardized to
contain the hemagglutinins of influenza virus strains (i.e., typically two type
A and one type B), representing the influenza viruses likely to be circulating
in the U.S. in the upcoming winter.

Clinical Studies

Efficacy Against Laboratory-Confirmed Influenza

The efficacy of Flublok (trivalent formulation) in
protecting against culture-confirmed influenza illness was evaluated in a
randomized, observer-blind, placebo-controlled multicenter trial conducted in
the U.S. during the 2007-2008 influenza season in adults 18-49 years of age
(Study 1). (1)

Study 1 enrolled and vaccinated 4648 healthy adults (mean
age 32.5 years) randomized in a 1:1 ratio to receive a single dose of Flublok
(n=2344) or saline placebo (n=2304). Among enrolled subjects, 59% were female,
67% were white, 19% African-American, 2% Asian, < 1% other races, and 11% of
Latino/Hispanic ethnicity. Culture-confirmed influenza was assessed by active
and passive surveillance for influenza-like illness (ILI) beginning 2 weeks
post-vaccination until the end of the influenza season, approximately 7 months
post- vaccination. ILI was defined as having at least 2 of 3 symptoms (no
specified duration) in the following categories: 1) fever ≥ 100°F; 2)
respiratory symptoms (cough, sore throat, or runny nose/stuffy nose); or 3)
systemic symptoms (myalgias, arthralgias, headache, chills/sweats, or
tiredness/malaise). For subjects with an episode of ILI, nasal and throat swab
samples were collected for viral culture.

The primary efficacy endpoint of Study 1 was Centers for
Disease Control-defined influenza-like illness (CDC-ILI) with a positive
culture for an influenza virus strain antigenically resembling a strain
represented in Flublok. CDC-ILI is defined as fever of ≥ 100°F oral accompanied
by cough, sore throat, or both on the same day or on consecutive days. Attack
rates and vaccine efficacy (VE), defined as the reduction in the influenza rate
for Flublok relative to placebo, were calculated for the total vaccinated
cohort (n=4648).

The pre-defined success criterion for the primary
efficacy analysis was that the lower bound of the 95% confidence interval (CI)
of VE should be at least 40%. Vaccine efficacy against antigenically matched
culture-confirmed CDC-ILI could not be determined reliably because 96% of the
influenza isolates obtained from subjects in Study 1 were not antigenically
matched to the strains represented in the vaccine. An exploratory analysis of
VE of Flublok against all strains, regardless of antigenic match, isolated from
any subject with an ILI, not necessarily meeting CDC- ILI criteria,
demonstrated an efficacy estimate of 44.8% (95% CI 24.4, 60.0). See Table 4 for
a presentation of VE by case definition and antigenic similarity. Protein
Sciences Corporation Influenza Vaccine Package Insert BLA STN 125285 Flublok PI
(V4.3), 2016 Page 13 of 16

*In Study 1 (NCT00539981) vaccine efficacy analyses were
conducted on the Total Vaccinated Cohort (all randomized subjects who received
study vaccine according to the treatment actually received and who provided
data). Vaccine efficacy (VE) = 1 minus the ratio of Flublok/placebo infection
rates. 1 Determined under the assumption of Poisson event rates, according
to Breslow and Day, 1987. 2 Meets CDC influenza-like illness (CDC-ILI) defined as fever of
≥ 100°F oral accompanied by cough and/or sore throat, on the same day or
on consecutive days.3 Primary endpoint of trial. 4 All culture-confirmed cases are considered, regardless of whether
they qualified as CDC-ILI. 5 Secondary endpoint of trial. 6 Exploratory (prespecified) endpoint of trial.

The efficacy of Flublok Quadrivalent is relevant to
Flublok (trivalent formulation) because both vaccines are manufactured using
the same process and have overlapping compositions (see DESCRIPTION).

Study 6 evaluated the efficacy of Flublok Quadrivalent in
a randomized, observer-blind, active-controlled, multi-center trial conducted
during the 2014-2015 influenza season in adults 50 years of age and older. A
total of 8963 healthy, medically stable adults (mean age 62.5 years) were
randomized in a 1:1 ratio to receive a single dose of Flublok Quadrivalent
(n=4474) or a U.S.-licensed quadrivalent inactivated influenza vaccine
(Comparator, Fluarix Quadrivalent, manufactured by Glaxo SmithKline) (n=4489).
Among randomized subjects, 58% were female, 80% white, 18%
black/African-American, 2% other races, and 5% of Hispanic/Latino ethnicity. A
total of 5186 (60%) subjects were 50-64 years of age and 3486 (40%) were
≥ 65 years of age. Real-time polymerase chain reaction (rtPCR) -confirmed
influenza was assessed by active and passive surveillance for influenza-like
illness (ILI) beginning 2 weeks post-vaccination until the end of the influenza
season, approximately 6 months post- vaccination. ILI was defined as having at
least one symptom (no specified duration) in each of two categories of
respiratory and systemic symptoms. Respiratory symptoms included sore throat,
cough, sputum production, wheezing and difficulty breathing. Systemic symptoms
included fever > 99°F ( > 37°C) oral, chills, fatigue, headache and
myalgia. For subjects with an episode of ILI, a nasopharyngeal swab sample was
collected for rtPCR testing and reflex viral culture of rtPCR-positive samples.

The primary efficacy endpoint of Study 6 was rtPCR-positive,
protocol-defined ILI due to any strain of influenza. Attack rates and relative
vaccine efficacy (rVE), defined as 1 - [Attack rate Flublok Quadrivalent/
Attack Rate Comparator], were calculated for the total efficacy population
(n=8604) for the primary efficacy endpoint and for several alternative efficacy
endpoints (Table 5). Antigenic and phylogenetic evaluations of the similarity
(“matching”) of clinical isolates to vaccine antigens were not performed. CDC
epidemiological data for the 2014-2015 influenza season indicated that
Influenza A (H3N2) viruses predominated and that most influenza A/H3N2 viruses
were antigenically dissimilar while A/H1N1 and B viruses were antigenically
similar to vaccine antigens.

PATIENT INFORMATION

Flublok stimulates the immune system to produce
antibodies that help protect against influenza viruses contained in the
vaccine, but does not prevent other respiratory infections.

Instruct the vaccine recipient to report any adverse
events to their healthcare provider and/or to the Vaccine Adverse Event
Reporting System (VAERS).

Provide the vaccine recipient with the Vaccine
Information Statements which are required by the National Childhood Vaccine
Injury Act of 1986 to be given prior to vaccination. These materials are
available free of charge at the Centers for Disease Control (CDC) website (www.cdc.gov/vaccines).